The Internet of Things (IoT) refers to uniquely identifiable objects and their virtual representations in an Internet-like structure. Radio-frequency identification (RFID) was seen as a prerequisite for IoT devices in the early days. If all objects and people in daily life were equipped with identifiers, they could be managed and inventoried by computers. By using IoT devices, a person's ability to interact with objects can be altered remotely based on immediate or present needs.